Terahertz epsilon-near-zero graded-index lens.
Victor Torres,Victor Pacheco-Peña,Pablo Rodriguez-Ulibarri,Miguel Navarro-Cia,Miguel Beruete,Mario Sorolla,Nader Engheta +6 more
TLDR
A complete theoretical analysis based on the waveguide theory and Fermat's principle is provided and numerical simulation results of two-dimensional and three-dimensional lenses, made of PEC and aluminum, respectively, and working in the terahertz regime, which show good agreement with the analytical work.Abstract:
An epsilon-near-zero graded-index converging lens with planar faces is proposed and analyzed. Each perfectly-electric conducting (PEC) waveguide comprising the lens operates slightly above its cut-off frequency and has the same length but different cross-sectional dimensions. This allows controlling individually the propagation constant and the normalized characteristic impedance of each waveguide for the desired phase front at the lens output while Fresnel reflection losses are minimized. A complete theoretical analysis based on the waveguide theory and Fermat's principle is provided. This is complemented with numerical simulation results of two-dimensional and three-dimensional lenses, made of PEC and aluminum, respectively, and working in the terahertz regime, which show good agreement with the analytical work.read more
Citations
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Enhanced third harmonic generation from the epsilon-near-zero modes of ultrathin films
Ting S. Luk,Domenico de Ceglia,Sheng Liu,Gordon A. Keeler,Rohit P. Prasankumar,Rohit P. Prasankumar,Maria Antonietta Vincenti,Michael Scalora,Michael B. Sinclair,Salvatore Campione +9 more
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Antireflection temporal coatings
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Effective medium concept in temporal metamaterials
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Near-zero-index wires.
Luigi La Spada,Lucio Vegni +1 more
TL;DR: Analytical and numerical results will confirm that the use of near-zero cover materials leads to extraordinary properties in terms of field configurations, low attenuation, and bandwidth.
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Experimental realization of an epsilon-near-zero graded-index metalens at terahertz frequencies
Victor Pacheco-Peña,Victor Pacheco-Peña,Nader Engheta,Sergei A. Kuznetsov,Sergei A. Kuznetsov,Alexandr Gentselev,Miguel Beruete,Miguel Beruete +7 more
TL;DR: In this article, a fully metallic, epsilon-near-zero (ENZ) graded-index metalens working in the terahertz regime with a narrow quasisymmetric focus, high power enhancement, and a large focal length is presented.
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